EXPERIMENTAL INOCULATION. 359 



disturbance in the central nervous system, with a possible 

 tendency to degeneration in its specialised cells. The latter 

 change may either be a consequence of the former, or both 

 may be due to a common cause. While such appearances 

 are often seen in the nervous system, cases occur where they 

 are not at all well marked, or where they may be altogether 

 absent. In the other organs of the body there are no 

 constant changes. 



We have said that the general distribution of pathogenic 

 bacteria throughout the body is probably a relative pheno- 

 menon, and that bacteria usually found locally may occur 

 generally and vice versa. With regard to the tetanus 

 bacillus it is, however, probably the case that very rarely, if 

 ever, are the organisms found anywhere except in the local 

 lesion. 



(b} The artificially-produced Disease. The disease can 

 be communicated to animals by any of the usual methods 

 of inoculation, but does not arise in animals fed with bacilli 

 whether the latter contain spores or not. Kitasato found 

 that pure cultures, injected subcutaneously or intravenously, 

 caused death in mice, rats, guinea-pigs, and rabbits. In 

 mice, symptoms appear in a day, and death occurs in two or 

 three days, after inoculation with a loopful of a bouillon cul- 

 ture. The other animals mentioned require larger doses, and 

 death does not occur so rapidly. The symptoms generally 

 are those of the natural disease, the spasms beginning in the 

 muscles nearest the site of inoculation. After death there is 

 found slight hyperaemia without pus formation, at the seat 

 of inoculation. The bacilli diminish in number, and may 

 be absent at the time of death. The organs generally show 

 little change. 



Kitasato acknowledges that in these earlier experiments 

 the quantity of culture medium injected along with the 

 bacilli, already contained enough of the poisonous bodies 

 secreted by the bacilli to cause death. The symptoms 

 came on sooner than by the improved method mentioned 

 below, and were, therefore, due to an intoxication with the 

 toxines present, not to the inoculation with the bacilli. In 



